How can someone tell if a bolt ejector is worn without the use of a go-no-go gage? I would also like to check for prpoer head space if possible.
I have no idea what a "bolt ejector" is.
The rifles ejector is welded into the left side of the receiver.
You can check it for proper size by pulling the bolt back until the ejector is even with the bolt face and simply look. The ejector should almost touch the side of the bolt face and should be properly shaped with no excessively rounded off front corner.
If you mean the extractor, you just check it for chips or excessive wear. Also check the spring for rust or impacted fouling.
The best check is to fire the rifle and watch ejection. The AK's eject rather violently and it's not unusual for the case to be thrown 30 feet.
If the rifle starts ejecting with less force, or starts failing to extract from the chamber, you may have a wearing extractor or ejector.
To check head space you need a set of head space gages. You can buy these from Brownell's.
To use, you clean the chamber and bolt face VERY clean and remove the extractor from the bolt.
]http://www.brownells.com/.aspx/cid=0/k=head+space%5d/t=P/ksubmit=y/Products/All/search=head_space]